Fluid muffler



OGL 18 19381 c. H. sTEENsT'RUP 2,133,876

FLUID MUFFLER Original Filed Feb. 17, 1937 Pig. 1.

1n\/a=:r1c.or` Carl H. Steenstrup,

His Attorney.

'Patented Oei. '18,1938

UNITED STArEs z ,isam num Mumna cui n. vsimilia-up, seaman, N.

to General Electric Company.'

New York Y., assigner a corporation et origini application sebi-nr; 11,mi. saisi N.

125.206. Divided and this application August 25, 1937, Serial No.181,075

reclaim.

frigerating machines of the compression type.

A refrigerating machine of the compression type having an'improvedintake muiiier of this construction is described and claimed in mycopending application Serial No. 126,206, filed February 17, 1937, ofwhich this application is a division, both applications beingassigned-to the General Electric Compa Compression type refrigeratingmachines are frequently provided with a compressor and a driving motorenclosed in a casing which is preferably hermetically sealed, thisobviating the *necessity of using connections with packing glands or thelike between the motor and compressor, and minimizing leakage ofrefrigerant from the machine, as any gaseous refrigerant which escapesfrom the compressor is 'coniined in the enclosing casing. It isdesirable that the enclosing casing be provided with a lubricantreservoir for containing a body of lubricant which is recirculated tothe bearing and moving parts of the motor and compressor duringoperation of the machine without the necessity of variation andreplenishment, thus simplifying the maintenance of the machine. Inorderv to minimize the transmission of operating noises of thecompressor through the enclosing casing to a reingerator cabinet 1i isdesirable um an intake muffler be associated with the intake port of thecompressor.

During the operation of a refrigerating machine of this type it is veryimportant that no appreciable quantity of the body of lubricantcontained in the lubricant reservoir formed in the enclosing casing bedrawn into the cylinder of the compressor through the intake muilier, asthe presence of lubricant in the compressor cylinder would give rise toexcessive pressures in the cylinder resulting in damage' to the valvesof the compressor, lubricant being a non-compressible fluid. In actualpractice, it is difficult to prevent lubricant from being drawn into thecylinder of the compressor as the body of lubricant containedin thelubricant reservoir formed in the enclosing casingv often becomes frothyand rises considerably above its normal operating level in the enclomngcasinginto the intake zone of the intake muiiler. Furthermore, duringthe assembly'and shipment of such a refrigerating machine the enclosingcasing often becomes tilted from its normally upright position allowinga portion' of the body of lubricant contained in the lubricantreservoirto spill into the intake muiiler, from which it is drawn intothe cylinder ofthe compressor when the machine is started.

It is an object of my invention to provide an improved intake muiiierconstruction for compress ion type refrigerating machines or the likewhich embodies an arrangement providing for the escape from the 'intakemumer of any lubricant accumulated therein.-

Another object of my invention is to provide an improved fluid muilierfor refrigerating machines or the like which is compact and rugged inconstruction, which requires a minimum number of parts, and which iseconomical to manufacture.

Further objects and advantages of my invention will become apparent asythe following description proceeds, and the features of novelty whichcharacterize my invention will be pointed out-with particularity in theclaims annexed to and forming a part of this specification.

For a better understanding of my invention reference may be had to theaccompanying drawing, in which Fig. 1 is a side elevation, partly insection, of a refrigerating machine provided with an intake muilierembodying my invention;

Fig. 2 is a vertical sectional view of the intake` muiiler shown in Fig.l; Fig. 3 isa sectional view of the intake muiiier along the line 3 3 ofFig. 2; Fig. 4 is a vertical sectional view ofva modied form of theintake muiiier shown in' Fig. 2; Fig. 5 is a plan view of the intakemuiiier shown in Fig. 4; and Fig. 6 is a fragmentary side elevationalview taken in the direction of the arrow I in Fig. 1 ci thereirigerating machine.

Referring to the drawing, in Fig. 1 I have shown. a refrigeratingmachine of the household type provided with a hermetically sealed casingi0 made of an upper casing section I i and a lower casing section i2,the adjacent edges of these casing sections being welded together at ilover a reinforcing ringl il. The casing sections ii and l2 arepreferably made of steel and are mounted on a removable cabinet top Il.A refrigerant compressor I6' and an electric driving motor i1 thereforare enclosed `,within the hermetically sealed casing III. The compressori6 is secured to the top of the driving motor il by a series 'of boltsIl, thus forming a compact unitary structure. 'Ihis unitary structure ismounted in the casing I0 on three vertical springs I9, 2l and 2l. Theupper ends of the springs i9, 2l and 2i are secured to feet 22, 23 and24, respectively, these As best shown in 1713.6, the driving motor |15"has a substantially vertically disposed shaft 3l which extends above theupper end shield of the driving motor and reciprocates a compressorpiston 26 in a substantially horizontal cylinder of the compressor I6through a suitable driving connection til. Preferably; the drivingconnection is of the Scotch yoke mechanism type including a crank pin 28and a cross-head 29 slldably carried by the end of the piston 26. Acounterweight 36 is disposed eccentric with respect to the center lineof the vertical shaft and counteracts the dynamic unbalancing effect ofthe crank pin 28V l0 and the reciprocating piston 26 upon the unitarystructure comprising the compressor I6 and the driving motor Il, duringoperation of the machine. Intake and exhaust ports are provided in thecompressor cylinder in communication with 15-amuiile box 3i secured tothe compressor i6 adthe lower end of a depending exhaust conduit 36,

A the upper end of which is securedto .the muilie 25 box 3l incommunication withj the exhaust port of the cylinder of the compressorI6. A plurality of `relatively long restricted tubes 3l havingreturn-bend-portions secured in openings provided in the intake muiller33 provides communication 30 between the upper portions of the enclosingcas- V 'Ming i0 and the interior of the intake muilier 33.

When the refrigerating machine is first started the body of lubricantcontained in the lubricant reservoir i2a formed'in the enclosing casinglil 'becomesfrothy and rises above its normal level in the enclosingcasing due to the reduction of the pressure within the enclosing casing,causing the gaseous refrigerant absorbed inthe body of lubricant toseparate therefrom. Even though the body of lubricant contained in thelubricant reservoir i2a` becomes frothy and rises in the enclosingcasingit when the machine is started or Y any time during the operation of themachine, it cannot completely iiii the enclosing casing as it will bebroken up when its upper level reaches the horizontal plane of movementof the eccentrically disposed counterweight 3B, indicated by the brokenline 38 in the upper portion of the enclosing casing. The `frothylubricant coming 5o into contact with thecounterwcight 30 is thrownoutwardly in a radial direction in a thin sheet substantially in theplane indicated by the broken Y line [,38 dueto centrifugal force,whichfu'rther Y prevents theV frothy lubricant in thelower portion ofthe' enclosing casing il) from rising above this plane.l The movement ofthe counterweight 36 in the plane substantiaiy normal to the vertical ishaft 42li thus suppresses frothing of the lubricant in the upper'portion of the enclosing casing and w establishes a zonesubstantiallyfree of frothy lubricant in the upper portion of theenlosing casing above theplane indicated bythe broken i line 38." Theinlet ends of the tubes 31 communicate with this zone in the upperportion of the Y n enclosing casing l0 above the plane indicated by thebroken liney 38, thereby positively finsuring that no frothylubricant bedrawn into the intakeniuiller 33 alongwith the gaseous refrigerantdur'ing the operation of thevmachine Y, Theabove describedarrangementfor prevent-V lngfrothy lubricant from being drawn intothe intake oftirey cnpressor is described and claimed in. above-mentioned co'pendingapplication serreruegraeaos, med February 17,1937.

g the piston'zi in the compressor cylinder is retracted on its suctionstroke the pressure within the cylinder is reduced and gaseousrefrigerant 1s Ydrawn into the cylinder from the upper portion of theenclosing casing I0 through the intake muffler 33, the mule box 3| andthe intake 5 valve of the cylinder. When the piston 26 in the compressorcylinder is moved in the opposite (lirection on its compression strokethe gaseous refrigerant within the cylinder is compressed and dischargedthrough the exhaust valve of the cyll0 inder and the muie box 3l intothe exhaust muilier; 35. The compressed gaseous refrigerant passes fromthe exhaust muiiler 35 through a con# duit 39 to a condenser 40 which iscooled by natf ural draft and which surrounds the enclosing 15 casingl0, the condenser having a passage 4| therein preferably divided intoupper and lower portions .which are connected in series by a conduit 42.The compressed gaseous refrigerant is liquefied in the condenser 40andows therefrom zo through a conduit 43 to a suitable ow controllingfloat valve 44.

Liquidrefrigerant is supplied from the iiovv controlling float valve 44`through a liquid line 45 to a sheet metal flooded type evaporator 46.'Ihe 25 evaporator 46 is supported in the food storagel compartment ofthe refrigerator cabinet by the heat insulated removable cabinet top l5.The liquid refrigerant contained in the evaporator 46 I is vaporized bythe absorption of heat from arti- 80 cles contained inthe food storagecompartment in which the evaporator is located and the vaporizedrefrigerant is collected in a cylindrical header 41 which is normallymaintained about half full of liquid refrigerant. The vaporizedrefriger- 35 ant which is accumulated above the level of the' liquidrefrigerant in the header 4l is returned to the interior of theYenclosing casing IIJ through a suction conduit 48 which communicateswith the header 4l above the normal liquid level therein. 40 It will benoted that the discharge end 48a of the suction conduit 48 is locatedabove the vnormal level of the body or lubricant contained in the.lubricant reservoir l2a formed in the lower cas-V ing section l2 of theenclosing casing l0. The` 45 'vaporized gaseous refrigerant thusdischarged in the enclosing casing lli is again drawn into the intakemuier 33 through the tubes 3l communieating With the zone substantiallyfreeof frothy lubricant in the upper portion of thev enclosing 50 casingI0, and the cycleabove described is repeated until the compartment inwhich the evaporator 46 is located is cooled to the desired tem-lpcrature. It will be noted that the upper p'ortion of the enclosingcasing I0, above'the level of 55 the body of lubricant in the lubricantreservoir |2a therein, is normally filled with low pressure gaseousrefrigerant. Any gaseous refrigerant which may have been trapped in thebody of lubricant while the machine is at rest will be re- 60 leasedfrom this body of lubricant after the machine has run a short time andwill again be mingled with the lo'w pressure gaseous refrigerantthereabove.. f

Preferably, the intakemuler 33 is formed of 65 sheet-metal, one form ofwhich is shown in Figs. 2 and 3,and comprises a series of similar casingsec-v tions Vsecured together. In the illustrated formf' of the intakemuiierV only an' upper casing sec'- tion 6U and a similarlower casing 6Iare shown 70 in series, although it will be understood vthat any desirednumber of casing sections may be employed `in sries to'obtain themuilling effect desired. Each of the casing sectionsA is of cupshapedconfiguration comprising an end wall, a

cylindrical side wall and an outwardly flared open end., The outwardlyflared open end 32 of the upper casing section III receives the end wall33 and rmly grips the cylindrical side wall of the lower casing section8|. The upper and lower casing section may be soldered or otherwiserigidly secured together. However, I'prefer that the nt between theoutwardly ilared open end ot vthe upper casing section and thecylindrical side wall of the lower casing section be suillciently tightto hold the muilier casing in assembled relation by friction. The endwall 83 of the lower casing 6| constitutes a transverse partition in themumer casing and is provided with a restricted passage i 64therein'aiording communication between upper and lower chambers 85 and88, respectively, in the muiiler casing. A plate 81 is rigidly securedin the outwardly ilared open end 88 of the lower casing section 6| bybrazingfonthe like. The end of the returnbend portion` of each of thetubes 31 is secured by brazing in openings 83 provided in the plate 81.'I'he lower end of the depending intake conduit 34 is secured by brazingin a restricted passage 10 formed in the end wall 1| of the upper casingsection 80. The

intake conduit 34 has an external diameter such that it may be snuglyreceived in either of the restricted passages 1li or 84vin the upper orlower casing section 60 or 6 i, respectively, so that when the intakemui'iler is assembled any of a large number of similarly formedcasingsections may be placed in any order in-the series. Preferably,each of the tubes 31 is provided with an inlet end or opening 12disposed at a relatively. sharp angle with respect to the axis of theextended portion of the tube in order to minimize the whistling noisesproduced by the entrance of the gaseous refrigerant into the tube. Also,the end oi.' the return-bend portion of each of the tubes 31 received inthe opening 69 formed in the` plate 31 is provided with an outlet end oropening 13 disposed at a relatively sharp angle with respect to theyaxis of the return-bend portion of the tube in order to further minimizethe whistling noises produced by the gaseous refrigerant emerging fromthe tube into the lower chamber 88 in the munler casing. l

A restricted aperture 14 is provided in the plate 61 which aiordscommunication between the'lower chamber 68 in the mumer casing and theinterior of the enclosing casing I8 to provide for the escape from thelower chamber 88 of any lubricant'accumulating therein, and to allowthis lubricant to be drained back into the lubricant reservoir I2aformed in the lower casing section I2. The area of the restrictedaperture 14 is small as compared to the" area of the tubes 31 in orderto insure that the pressure -drop through the restricted aperture 14 isrelatively .great as compared to the pressure drop through the tubes31,. 'I'his arrangement insures that substantially no gaseousrefrigerant will be drawn into the lower chamber 88 of the mufller n therestricted aperture 14, yet lubricant accumulating therein will bepermitted to escape.

kDuring theY operation of the refrigeratingrmazhine, gaseous refrigerantis drawn into the lower :hamber 88 ofthe intake muiller 33 from the zoneiubstantially free of frothy lubricant in the upper Jortion of theenclosing casing i8 through the 'elatively longrestricted tubes 31having returnend portions. The gaseous refrigerant then lows from thelower chamber 88 through the restricted passage 84 formed in the endwall 83 f the lower casing section 8| into the upper ybe drained casingthrough ings Y 3 chamber 8l of the muiiier casing. The gaseousrefrigerant is thendrawn from the upper chamber 8l through the dependingintake conduit 34 into the munie box 3| and the intake of the compressorI8. Any lubricant gaining entrance into the muiller casing 33 willescape through the restricted aperture 14 provided in the plate Bland Inan intake mufiler such as I have illustrated in Figs. 2 and 3, designedfor use in conjunction with a sulphur dioxide refrigerant compressor,two tubes 31 should be employed to conduct gaseous refrigerant into themumer casing 33: Each of the tubes should have a return-bend portion andan overall length approximately 50 times the internal diameter thereofsoA that an extended reverse-flow muiliing path of restrictedcross-section is formed between the inlet and outlet ends of the tube.The columns of gaseous refrigerant in these tubes have a sufficientlyhigh inertia that ther energy of the wave motion set up in the gaseousrefrigerant within the depending intakeconduit 34 and the chambers 85and 88 in the'muiiler casing is substantially all dissipated in movingsuch columns of gaseous refrigerant. 'Ihe volume of the mumer chambers63 and 88 should be relatively large as compared to that of the tubes31, both the internal diameter and the height of each of the chambersbeing of the order of` 9 times the internal diameter of the tubes 31.Also. the volume of the muiller casing should be somewhat larger thanthe volumetric displacement of the piston in the cylinder lo i' 'thecompressor in order to provide areserve supply` of gaseous refrigerantinthe muiiler casing thereby minimizing the surges of gaseousrefrigerant into the compressor on the suction stroke and theaccompanying vibratory disturbances.

In Figs 4 and 5 I'have shown a modiiled form Iof the intake muirler 33comprising complemenary upper and lower casing sections 88 and 8|,respectively, of substantially cup-shaped contiguration. 'Ihe uppercasing section 88 is provided with an outwardly ared open end 82 and thelower casing section 8| is provided with an inwardly flared open end 83,the inwardly flared open end 83 being received and firmly gripped withinthe outwardly flared open end 82. These casing sections may be brazed orotherwise rigidly securedl together. However, I prefer that the fltbetween the outwardly flared open end 82 and the inwardly ,flared openend 83 be sufiicif ently tight to hold the mulder casing in assembledrelation by friction. A transverse partition 84 is arranged in ltheupper casing section 80 in abutting relationship with the inwardlyflared' l open end 83 of the lower casing section 8|. The partition 84is provided with a restricted passage' 88 therein forming communicatingupper and lower chambers 88 and l1 in the muiiler casing. The end wall38 of the upper casing section 80 is provided with two spaced. apartopenings 88 in vertical alignment with two lspaced apart open- 30providedin the transverse partition 84 through which two relatively longrestricted tubes 3| are inserted into the mufiler casing. Each of thetubes 8| extends through the end Wall 88 of the upper casing section 80,the upper chamber 88, and the transverse partition 84 into the lowerchamber 81.` The tubes 9| are of sumcient length so as to communicatewith the zone substantially free of `frothy lubricant in the upperportion of the enclosing casing I8, when the intake muil'ler illustratedin Figs. 4 and 5 is employed in the refrigerating machine. Preferably,

back into the lubricant reservoir |2'a.

Y each of the tubes 9| is provided with an inlet end or opening 92disposed at a relatively sharp angle with respect to the axis of thetube and an outv let end 93 disposed adjacent the end'wall 94 of thelower casing sectlon l depending intake conduit 34 is secured in anopening 95 provided in the end wall 88 of the upper casing section 88.

I chamber 8l of the muffler casing through the re- The end wall 94 ofthe lower casing section 8| is provided with a centrally disposed andinwardly extendingindentation 96 which defines an annular reservoir B'lin the end wall 94. A restricted aperture 98 is provided in the inwardlyextending indentation 9,6 which affords communication between the lowerchamber 8l and the interior of the enclosing casing i0 to provide forthe escape from the lower chamber 87 of any lubricant accumulatedtherein, and to permit this lubricant to be drained back into thelubricant reservoir |20. formed in the lower casing section i2. It willbe observed that the lower ends 93 oi the tubes 9| are arranged out ofalignment with the restricted aperture, 98 provided in the inwardlyextending indentation 96 to prevent the gaseous refrigerant emergingfrom the outlet ends 93 of the tubes 9| from interfering with the escapeof lubricant accumulating in the annular reservoir 9i through therestricted aperture 98. The area of the restricted aperture 98 is smallas compared to the area of the tubes 9| in order to insure thatthepressure drop through the restricted aperture 98 is relatively great ascompared to the pressure drop throughvthe tubes 8|.

This arrangement insures that substantially no gaseous refrigerant willbe drawn into the lower stricted aperture 98, yet lubricant accumulatingvtherein will be permitted to escape.

The lower end of the f During the operation of therefrigeratingmathrough the depending intake conduit 3G into the muniebox 8| and the compressor i6. Any lubricant gaining entrance into themuiiier casing 8| escapes through' the restricted aperture Q8 providedin the inwardly extending indentation @E and is drained back into thelubricant reservoir In an intake muiier such as I have illustrated inFigsA and'5, designed for use in conjunction with a sulphur dioxiderefrigerant compressor, two tubes 9| should be employed'to conductgaseous refrigerant into the mumer casing. Each of the tubes should havean overall length approximating 40 times the internaldiameter thereof sothat an extended muting path of restricted cross-section is formedbetween the inlet and outlet ends of the tube. Also, the outlet ends ofthe tubes should extend into the munier casing' in close proximity tothe end wall 8f3 of the lower casing section 8| so that the end wallserves as a baille for the gaseous refrigerant emerging from the tubesto reverse the direction of flow thereof. 'I'he columns of gaseousrefrigerant in these tubes have a suiiiciently high inertia. that theenergy of the wave motion set up in the gaseous refrigerant within thedepending inaisae're take conduit 34 andthe chambers 86 and 81 in themuflier casing is substantially all dissipated in moving such columns ofgaseous refrigerant.

The volume of the muilier chambers 86 and 81 I lshould be relativelylarge as compared to that of the tubes 9|, the internal diameter of eachof the chambersbeing of the order of 9 times the internal diameter ofthe tubes 9| and the overall height of the two chambers beingapproximately twice the diameter of the chambers. Also, the Volume ofthe muffler casing should be somewhat larger than the volumetricdisplacement ofthe piston in the cylinder of the compressor inorder. toprovide a, reserve supply of gaseous refrigerant in the muflier casingthereby minimizing the surges of gaseous refrigerant into the compressoron the suction stroke and the accompanying vibratory disturbances.

WhileI have shown aparticular embodiment of my invention in connectionwith a household type of refrigerating machine, I do not desire myinvention to be limited to the particular construction shown anddescribed, and I intend in thel appended claims to cover allmodifications with in the spirit and scope of my invention.

vWhat I claim as new and desire to secure by Letters Patent of theUnited States, is:

1. An intake muiiler for a refrigerant coni.-` pressor or the likecomprising a casing, means constituting a transverse partition in saidcasing and provided with a restricted passage therein forming aplurality of communicating chambersin said casing, means including arelatively long restricted tube communicating with one of said chambersfor conducting' gaseous refrigerant thereto, a restricted aperture insaid casing and arranged to provide for the escape from saidcasiny ofany lubricant accumulating therein, and means including a conduitcommunicating with another of said chambers for conducting the gaseousrefrigerant from said casing.

2. An intake muflier for a refrigerant compressor or the like comprisinga casing having side, top and bottom walls, means constituting atransverse partition insaid casing and provided with a. restrictedpassage therein forming communieating upper and lower chambers in saidcasing, means including a relatively long restricted tube communicatingwith said lower chamber for conducting gaseous refrigerant thereto, arestricted aperture in said bottom wall andarranged to provide for theescape from said lower chamber of any lubricant accumulating therein,and means including a conduit cunicating with said upper chamber'forconducting the gaseous refrigerant from said casing.

.3. An intake muiiier for a refrigerant compressor or the` likecomprising a casing, means constituting a transverse partition in saidcasing and provided with a restricted passage therein forming aplurality of communicating cham bers in said casing, a plurality ofrelatively long restricted tubes communicating with one of saidAchambers for conducting gaseous refrigerant thereto, each of said tubeshaving an inlet end disposed at a relatively sharp angle with'reE spectto the axis of the tube, a restricted apar ture in said casing andarranged to provide for the escape from said casing of any lubricantaccumulating therein, and a conduit communieating with another ofsaidchambers for conducting the gaseous refrigerant from said casing.

4. An intake mufiier for a refrigerant com-v pressor or the likecomprising a tubular casing having side,- top and bottom walls, meansconstituting a transverse partition in said casing and provided with arestricted passage therein formingcommunicating upper and lower chambersin said casing, means including a plurality of relatively long tubes ofrestricted cross-sectional area communicating with said lower chamberfor conducting gaseous refrigerant thereto, an aperture of restrictedcross-sectional areavin said bottom wall and arranged to provide for theescape from said lower chamberl of any lubricant accumulating therein,the cross-sectional area of said aperture being considerably less thanthe cross-sectional area of each of said tubes in order to insure thatthe pressure drop through said aperture is considerably more than thepressure drop through each of said tubes, and means including a conduitcommunicating with said upper chamber forconducting the gaseousrefrigerant from said casing.

5. An intake muiiier for a refrigerant compressor or the like comprisinga casing having side and end walls, means constituting a transversepartition in said casing and provided with a restricted passage thereinforming a plurality of communicating chambers in said casing, meansincluding a relatively long restricted tube havingv a return-bendportion secured in an opening in one of said end walls forfconductinggaseous refrigerant into one of said chambers, a restricted aperture ina wall -of said casing and arranged to provide for the escape from saidcasing of any lubricant accumulating therein, and means including aconduit communicating with another of said chambers for conducting thegaseous refrigerant from said casing.

6. An intake muffler for a refrigerant compressor or the like comprisinga casing formed of a series of similar casing sections secured to'-gether, each of said casing sections being substantially cup-shaped andhaving an outwardly flared open end receiving the end wall of the nextsucceeding casing'section, the end wall of each of said casing sectionspositioned intermediate the ends of said casing constituting atransverse partition in said lcasing and provided with a restrictedpassage therein forming communicating chambers in said casing, a platesecured in the outwardly flared open end of the casing section at oneend of said casing, a relain said one end of said casing, a restrictedaperture'in said casing and arranged to provide for the escape from saidcasing oi' any lubricant ac-A cumulating therein, and a conduitcommunicating with the chamber in the other end of said casing forconducting the gaseous refrigerant from said casing.

'1. An intake muiiier for a refrigerant compressoror the like comprisinga casing formed of similarupper and lower casing sections securedtogether. each of said casing sections being substantially cup-shapedand having an outf wardly flared open end. the outwardly flaredopen` endof said upper casing section receiving the end wall o'f said lowercasing section, the end wall of said lower casing section constituting atransverse partition in said casing and provided with a restrictedpassage therein forming communicating upper and lower Schambers in saidcasing, a plate secured in the outwardly nared open endofsaid lowercasing section. a

relatively long restricted tube having a returnbend portion secured inan opening in said plate for conducting gaseous refrigerant into saidlower chamber, a restricted aperture provided in said plate and arrangedto provide for the escape from said lower chamber of any lubricantaccumulating therein, and a conduit communicating with said upperchamber for conducting the gaseous refrigerant from said casing.

8. An intake munier fora refrigerant compressor or the like comprising acasing having side and end walls, means constituting a transversepartition in said casing and provided with a restricted passage thereinforming a plurality of communicating chambers in said casing, meansincluding a relatively long restricted tube extending into said casingthrough one of said end walls and said partition, said tube having anopen end adjacent said other end wall for conducting gaseous refrigerantinto one of said chambers, a restricted aperture in a wall of saidcasing and arranged to provide for the escape from said casing oi anylubricant accumulating therein, and means including a conduitcommunicating with another of said chambers for conducting the gaseousrefrigerant from said casing.

9. An intake mufiier for a refrigerant compressor or the like comprisinga casing having side, top and bottom walls, means constituting atransverse partition in said casing and provided with a restrictedpassage therein forming communicating upper and lower chambers in saidcasing, a relatively long restricted tube extending into said casingthrough said top wall and said partition, said tube having an open endadjacent said bottom wall for conducting gaseous refrigerant into saidlower chamber, a restricted aperture provided in said bottom wall out ofalignment with the open end of said tube and arranged to provide `forthe escape from said lower chamber of any lubricant accumulatingtherein, and a conduit secured in an opening in said top wall forconducting the gaseous refrigerant from said upper chamber.

10. An intake muiiier for a refrigerant compressor or the likecomprising a casing formed of complementary cup-shaped casing sectionssecured together, one of said casing sections having an inwardly flaredopen end, the other of said casingsections having an outwardly flaredopen end receiving the inwardly dared open end .of said one casingsection, a transverse partition arranged in said other casing section inabutting relationship with the inwardly flared open end of said onecasing section, said partition being provided with a restricted etherein forming communicating chambers in said casing, a

plurality of relatively long restricted tubes ex-v tending into saidcasing through the end wall of v said other casing'section and saidpartition, each said casing.

CARL H. BTIINBTRUP.

